Radeon X850 XT Platinum Edition is the fastest graphics chip from ATI and we got an AGP board sample from ATI for reviewing. Since NVIDIA won’t release a GeForce 7800 GTX version for the AGP bus, theoretically this is the fastest VGA available for the AGP bus. Let’s see if that is true on our review.

All major video cards released recently are for the new PCI Express bus. The problem is that you need to upgrade your computer to have use a PCI Express-based video card and you may already have a terrific computer but based on the AGP bus and don’t want to change your motherboard or face a major upgrade in your system.

That’s were the AGP version of cards like the Radeon X850 XT Platinum Edition comes in place. It will allow you to reach a high-end performance without the need to move to the PCI Express platform.

You can see in our tutorial ”ATI Chips Comparison table“ the difference between this chip and the other chips from ATI, while on our tutorial ”NVIDIA Chips Comparison Table“ you can compare it to its competitors from NVIDIA. It is very important to keep in mind that NVIDIA chips from series 6 and 7 use a Shader 3.0 engine (DirectX 9.0c), while ATI chips still use Shader 2.0 (DirectX 9.0).

It is always important to remember that the ”memory clock“ column from these tables informs the chip manufacturer (ATI or NVIDIA) recommended clock. In some cases, specially on cheaper video cards, the card manufacturer uses simpler memory chips (in order to cut the board price) and lower memory clocks (compatible with the memory chip used), making the board to achieve a lower performance compared to boards that use the same graphics chip but with their memory chips running at the chip manufacturer recommended clock. Because of that, we always run PowerStrip software in order to check if the video card memory is running at the standard clock set by the chip manufacturer or running at a lower clock rate.

The reviewed Radeon X850 XT Platinum Edition reference model from ATI runs at 540 MHz for the chip and 1.18 GHz for the memory.